public static DiscoveryNode newNode(String nodeId, Map<String, String> attributes) {
        return new DiscoveryNode(
            "",
            nodeId,
            new TransportAddress(TransportAddress.META_ADDRESS, portGenerator.incrementAndGet()),
            attributes,
            Sets.newHashSet(DiscoveryNodeRole.MASTER_ROLE, DiscoveryNodeRole.DATA_ROLE),
            Version.CURRENT
        );
    }